When my company pursues slogan creation, we always present two options.

An extremely short version, based on no more that four syllables. It’s meant for print only, so the viewer can read and retain it quickly. But it’s never actually said or spoken aloud.

Nike “Just do it”

Studio7 “It Tickles” (follow with baby giggles if spoken)

Enchanted Attic, “I Love this store!”

But for radio, video, where there is a spoken identity, we attempt a jingle with original tune.

“For a hole in your roof, or a whole new roof, Fredrick Roofing” Follow with phone and web info. The idea is to get the jingle stuck in someone’s head. If jingles aren’t your thing, then at least apply a poetic cadence so it rolls off the tongue. Similar to the way a good comedian delivers a joke. Consider timing.

I’ve written ad slogans for companies big and small for 40 years, and I NEVER found any rules that consistently worked. Personally, I consider the value of slogans and taglines in today’s communications environment of non-stop hype and babble greatly over-estimated. But having said that, I consider the best kind of slogan one that captures the essence of the brand or company in the fewest number of words. Your example, “Just Do It,” is a classic example of this. And though I don’t think it sells one additional pair of shoes, it’s a great hook for advertising and marketing the brand.